#include<iostream>
using namespace std;
int main(){
	int n;
	cin>>n;
	int f[n];
	f[0]=1;f[1]=1;
	for(int i=2;i<n;++i){
		f[i]=f[i-1]+f[i-2];
		f[i]%=1000000007;
	}
	cout<<f[n-1];
	return 0;
}